Reef Fundamentals · Free course

The straight line into reefing

The hobby's advice is scattered everywhere. This is a single ordered path: ten short lessons that build on each other, from what a reef even is to keeping one stable for years.

Start lesson 1 10 lessons · ~81 min total

Module 1

The Invisible Foundations

Before livestock, before lighting: the water itself. What a reef actually is, the chemistry that runs it, and the living filter you have to grow first.

  1. Ocean Ecosystems: What a Reef Really Is A reef tank isn't a fish container, it's a miniature ecosystem, and your real job is keeping that whole system in balance. Lesson 1 · ~7 min
  2. Basic Chemistry: The Water Your Reef Lives In Corals don't need perfect numbers. They need steady ones. Stability of your key parameters beats chasing any single 'ideal' value. Lesson 2 · ~9 min
  3. The Nitrogen Cycle: Your Tank's First Job Cycling grows the bacteria that turn deadly ammonia into harmless nitrate. Until that's done, the tank cannot safely hold any life. Lesson 3 · ~9 min
  4. Microbiology: The Bacteria Running Your Reef You aren't really keeping corals: you're farming bacteria. A healthy, diverse microbial community is what makes everything else possible. Lesson 4 · ~8 min

Module 2

The Environment You Create

A reef tank is a machine for recreating a patch of ocean. These are the two levers you pull most: how the water moves and how it's lit.

  1. Water Movement: Why Flow Keeps a Reef Alive Flow is how a stationary coral eats, breathes and stays clean. Varied, gentle-to-moderate movement matters more than raw power. Lesson 5 · ~7 min
  2. Lighting: The Energy That Powers Corals For most corals, light literally is food. The goal is enough of the right spectrum, kept stable, not the brightest light you can buy. Lesson 6 · ~8 min

Module 3

The Living Reef

Now the life. What corals and fish need to thrive, how to feed a reef, and how to keep the whole system steady for the long haul.

  1. Coral Biology: What These Animals Really Are A coral is a colony of tiny animals partnered with algae and building a stone skeleton. Every care decision follows from those three facts. Lesson 7 · ~8 min
  2. Coral Nutrition: Feeding a Reef Without Feeding Algae Light is the main meal; feeding is the supplement. Feed deliberately and sparingly: every scrap that isn't eaten becomes algae fuel. Lesson 8 · ~8 min
  3. Fish Biology: Reef Fish and the System They Live In Every fish adds waste and personality to the system. Stock slowly, choose reef-safe species, and let your biofilter keep pace with the load. Lesson 9 · ~8 min
  4. Long-Term Reef Stability: Keeping It All Steady Success in reefing is a maintenance skill, not a setup skill. Consistent small actions over time beat any product, gadget or heroic fix. Lesson 10 · ~9 min

More coming soon

Video walkthroughs and self-paced courses are on the way. In the meantime, the deLIGHTful Coral blog has practical, tank-side guides that put these fundamentals into action.

Read the blog